Folding apparatus

ABSTRACT

The invention is directed to an apparatus and method for simultaneously folding the entire peripheral portion of a workpiece or part thereof. The apparatus comprises a shaping die having upper and lower elements, an elastomer sandwiched between the upper and lower elements, a press having upper and lower die members, and means for actuating the shaping die and press. The die elements and elastomer are formed with an internal hole which is adapted for reception of the upper and lower die members. The profiles of the die members conform substantially to the aperture profile of the internal hole and are in registration therewith. When the upper and lower elements are urged toward each other, the elastomer is compressed and bulges into the internal hole and engages the peripheral portion of the workpiece, whereby the entire margin of the workpiece or any portion thereof as desired is folded simultaneously.

[451 Aug. 21, 1973 FOLDING APPARATUS [75] Inventor: Alton R. Coplthorne,Rowley, Mass.

[73] Assignee: Boston Machine Works Company,

Lynn, Mass.

[22] Filed: Aug. 28, 1970 [21] Appl. No.: 67,773

[56] References Cited UNlTED STATES PATENTS 1,534,698 4/1925 Gansert etal. 72/57 X 2,487,494 11/1949 Taber 264/339 2,582,922 1/1952 Crowley etal..... 264/313 X 3,265,551 8/1966 Ananian et a1. 156/219 3,557,2771/1971 Brodersen et a1.. 264/339 X 3,608,058 9/1971 Coffman 264/3132,164,655 7/1939 Kleerup 156/493 X 2,954,725 10/1960 Palmer.... 93/58.lX 2,536,713 1/1951 Berg 156/196 5/1963 Bolles et a1. 156/479 9/1964 Wesaet al. 156/475 Primary Examiner-George F. Lestnes AssistantExaminer-Henry F. Epstein Attorney-Morse, Altman & Oates [57] ABSTRACTThe invention is directed to an apparatus and method for simultaneouslyfolding the entire peripheral portion of a workpiece or part thereof.The apparatus comprises a shaping die having upper and lower elements,an elastomer sandwiched between the upper and lower elements, a presshaving upper and lower die members, and means for actuating the shapingdie and press. The die elements and elastomer are formed with aninternal hole which is adapted for reception of the upper and lower diemembers. The profiles of the die members conform substantially to theaperture profile of the internal hole and are in registration therewith.When the upper and lower elements are urged toward each other, theelastomer is compressed and bulges into the internal hole and engagesthe peripheral portion of the workpiece, whereby the entire margin ofthe workpiece or any portion thereof as desired is foldedsimultaneously.

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T TORNE YS FOLDING APPARATUS BACKGROUND OF THE INVENTION 1. Field ofInvention The invention relates to folding and more particularly to anapparatus and method for simultaneously folding the margin of aworkpiece throughout its entire 360 periphery of any portion thereof.Examples of such workpieces are variously spaced ornaments for shoes,edges of books, or purses and pocketbooks or portions of shoe uppers.

2. Description of the Prior Art Various types of apparatus have beenproposed for folding the peripheral portion of workpieces. One typeemploys a sequential folding technique in which the peripheral portionof the workpiece is folded in discrete segments. Such folding apparatushave suffered from inefficiency due to the time required to complete afold throughout the entire periphery. Another type utilizes pivotedfolding dies by which the entire peripheral portion of the workpiece isfolded simultaneously. Such pivoted folding dies are complex inproduction and costly in operation. Other folding devices, such asdescribed in U.S. Pat. No. 3,073,141 are complex and require theservices of a skilled die sink craftsman.

SUMMARY OF THE INVENTION It is an object of the present invention toprovide a simple and efficient simultaneous folding apparatus which ischaracterized by a shaping die having upper and lower elements, anelastomer sandwiched therebetween, a press having upper and lower diemembers, and means for actuating the shaping die and press. The purposeof this apparatus is to simultaneously fold the entire or segments ofthe peripheral portion of a workpiece in the form of a sheet materialthat is composed, for example, material such as leather, vinyl polymer,etc. The shaping die and elastomer are formed with an internal openingand the upper and lower die members are adapted for reciprocablemovement within the aperture profiles of the elements of the shaping dieand of the elastomer and the profile of each die member of the pressbeing in registration. A slight clearance, typically ranging between0.01 and 0.10 inch between the aperture profiles and the profile of theupper die member is provided in order to enable reception therebetweenof the peripheral portion of the workpiece. The upper and lower diemembers are adapted for independent reciprocating movement within theopening. The upper and lower elements are adapted for compressing theelastomer sandwiched therebetween, the elastomer bulging into theinternal opening when compressed to fold the peripheral portion of theworkpiece reversely. Appropriate operation of the shaping die,elastomer, press and actuator means is such as to develop a fold in theperipheral portion of the workpiece and to press the superimposedperipheral portion in order to provide a permanent 360 fold.

The invention accordingly comprises the method and apparatus possessingthe construction, combination of elements, and arrangement of parts thatare exemplified in the following detailed description, the scope ofwhich will be indicated in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS Fora fuller understanding of thenature and objects of the present invention, reference should be had tothe following detailed description taken in connection with theaccompanying drawings wherein:

FIG. 1 is a perspective, partly in section, of a folded workpiece;

FIG. 2 is a top plan of a folding apparatus made according to thedrawing;

FIG. 3 is a section taken along the lines 3-3 of FIG. 1; and

FIG. 4(a) through (h) are diagramatic schematics illustratingconsecutive operational steps of the folding apparatus of FIG. 2. 1

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT As illustrated in FIG.1, the purpose of the invention is to produce from a' workpiece 46,using a simultaneous folding technique, a shaped ornament 45 having amargin portion 77 and a reversely bent portion 49.

A folding apparatus 10 of the type embodying the invention is shown inFIGS. 2 and 3 as being supported on a platform 12. Generally, thefolding apparatus comprises an elastomer 42 fonned with an internalopening 44, a press 14, and a shaping die 16. Press 14 includes an upperdie member 18 having an axial socket l9 and a lower die member 20 havingan axial socket 22. One end of a shaft 24 of an actuator 26 is securedin socket 19 and one end of a shaft 28 of an actuator 30 is secured insocket 22. In the illustratedem bodiment, upper die member 18 is drivenupwards and downwards in response to the movement of shaft 24 and lowerdie member 20 is moved upwards and downwards in response to movement ofshaft 28. Platform 12 is formed with a aperture 32 which is adapted forslidable engagement with shaft 28.

Shaping die 16 includes an upper element 34 and a lower element 36. Thetopside of upper element 34 is provided with a guide 38 which is adaptedfor positioning workpiece 46 in spaced relation to upper and lower diemembers 18 and 20, respectively. Shaping die 16 is held in spacedrelation to platform 12 by a spacer 40. Upper element 34, lower element36, spacer 40, and platform 12 is formed with an opening 47 which isadapted for slidable reception of a shaft 48 of an actuator 50. One endof shaft 48 is provided with a head 52, the profile of head 52 beingslightly larger than the opening in upper element 34. When actuator 50is energized, upper element 34 is pulled toward lower element 36. In theillustrated embodiment, the compressive movement of upper element 34against lower element 36 is accomplished by means of actuator 50 and anactuator 54. Actuator 54 is similar to actuator 50 and includes a shaft56 whichcorresponds to shaft 48, shaft 56 being slidably received in anopening 57. In the preferred embodiment, actuators 26, 30, 50, and 54are air driven. It is to be understood that, in alternative embodiments,the actuators are other than air driven, for example hydraulicactuators.

Elastomer 42, for example cast silicone rubber, is sandwiched betweenupper element 34 and lower element 36. Shaping die 16 and elastomer 42are formed with an internal opening defining a concentric hole 44 whichis adapted for reception of upper and lower die members 18 and 20, hole44 and the die members being in registration. As best shown in FIG. 2,the profile of lower die member 20 and the aperture profile of hole 44are slightly smaller than and corresponds substantially to the profileof workpiece 46. Upper die member 18 conforms substantially to theprofile of lower die member but is slightly smaller by an amount whichapproximates the thickness of workpiece 46. In consequence, theperipheral portion of workpiece 46 is turned upwardly about 90 as theworkpiece is drawn downwardly into hole 44 by the upper and lower diemembers. When upper element 34 is pulled toward lower element 36,elastomer 42 is compressed, whereby the elastomer bulges into hole 44and engages the upturned peripheral portion of the workpiece. Inconsequence, the upturned peripheral portion is folded greater than 90down to the prepared surface.

For a fuller understanding of the operation of the invention, referenceis now made to FIGS. 4(a) through (h). As shown in FIG. 4(a), a control58 is operatively connected to actuators 26, 30, 50, and 54 forselectively energizing the actuators in a specified sequence. Initiallyupper die member 18 is withdrawn from hole 44 and lower die member 20 ispositioned in planar relation to upper element 34. workpiece 46 isplaced on the lower die member and the upper element within the areadefined by guide 38.

As shown in FIG. 4(b), upper die member 18 is brought to bear againstworkpiece 46 and the lower and upper die members, working cooperatively,draw workpiece 46 into hole 44, the sidewalls of hole 44 being definedby the elastomer sandwiched between the upper and lower elements. Asworkpiece 46 is pulled downwardly into the hole, its peripheral portionis turned upwardly approximately 90. The downward movement of the diemembers continues until the upper surface of workpiece 46 is in planarrelation to the upper surface of lower element 36. Thereafter, upper diemember 18 is withdrawn from hole 44 and an adhesive 51 is applied at theedge of the interior face of the upturned periphery of workpiece 46. Itwill be readily appreciated that adhesive 51 is not required ifworkpiece 46 is composed of a material that is. pliant, but yet stiffenough to retain a fold or the adhesive may be applied previously.

In the next step, as shown in FIG. 4(d), upper element 34 is pulledtoward lower element 36 by actuators 50 and 54 in such a way thatelastomer 42 is compressed. In consequence, the elastomer bulges intohole 44 and engages the upturned peripheral portion, whereby theperipheral portion of workpiece 46 is folded reversely to 180. Asillustrated in FIG. 4 (e), the upper element is pulled away from thelower element, elastomer 42 returns to its original configuration andthe peripheral portion of the workpiece 46 remains folded. Thereafter,the upper die member is brought downwardly and presses the foldedperipheral portion of workpiece 46 into the shaped ornament illustratedin FIG. 1. As shown in FIGS. 4(3) and (h), lower die member 20 is raisedto the starting position shown in FIG. 4(a) and upper die member 18 isretracted away from workpiece 46. The shaped ornament is removed and theapparatus is available for folding another workpiece.

By way of an exemplary illustration, the apparatus shown in FIG. 1simultaneously folds the entire 360 peripheral portion of a workpiecehaving a circular profile. It is to be understood that, in alternativeembodiments, the workpiece to be folded has other than a circularprofile, for example a pear or a heart shaped profile and the fold maynot extend for the entire periphery. It will be readily appreciatedthat, in such alternative embodiments, the aperture profile of elastomer42, upper element 34, and lower element 36 and the profile of upper diemember 18 and lower die member 20 conform substantially to the profileof the workpiece to be folded and have the same relation thereto asdescribed in connection with the circular profile of workpiece shown inFIG. 1.

Since certain changes may be made in the foregoing disclosure withoutdeparting from the scope of the invention involved, it is intended thatall matter contained in the above description and depicted in theaccompanying drawings be construed in an illustrative and not in alimiting sense.

What is claimed is:

1. An apparatus for making a reverse fold in a workpiece, said apparatuscomprising:

a. an elastomer formed with an internal opening adapted for reception ofsaid workpiece, the aperture profile of said opening being slightlysmaller than and substantially conforming to the peripheral profile ofsaid workpiece;

b. means for positioning said workpiece within said opening, said meansfor positioning including upper and lower members, the profile of saidupper member being smaller than the aperture profile of said opening,said upper member having operative and inoperative positions, said uppermember engaging said workpiece when in its operative position anddisengaging said workpiece when in its inoperative position, said lowermember having operative and inoperative positions, said lower memberengaging said workpiece when in its operative position, said upper andlower members cooperating to .position said workpiece in planarrelationship to said elastomer, the peripheral portion of said workpiecebeing upturned when in planar relationship to said elastomer; and meansoperatively connected to said elastomer for compression thereof, saidcompression means including lower and upper elements, each said upperand lower element formed with a hole having a profile corresponding tosaid opening, said upper and lower elements having operative andinoperative positions, said elastomer being compressed when said upperand lower elements are in their operative positions, said compressedelastomer bulging into said opening and engaging the periphery of saidworkpiece and reversely folding the periphery of said workpiece, saidupper and lower elements are in their operative positions when saidupper member is in its inoperative position and said lower member is inits operative position.

2. The apparatus as claimed in claim 1 wherein said elastomer issilicone rubber.

3. The apparatus as claimed in claim 1 including means operativelyconnected to said compression means and positioning means for selectivecontrol thereof. 7 Y

4. An apparatus for making a reverse fold in a workpiece, said apparatuscomprising:

a. an elastomer formed with an internal opening adapted for reception ofsaid workpiece, the aperture profile of said opening being slightlysmaller than and substantially conforming to the peripheral profile ofsaid workpiece;

b. means for positioning said workpiece within said opening, said meansfor positioning including upper and lower members, the profile of saidupper member being smaller than the aperture profile of said opening,said upper member having operative and inoperative positions, said uppermember engaging said workpiece when in its operative position anddisengaging said workpiece when in its inoperative position, said lowermember defining a support for the workpiece, said upper and lowermembers cooperating to position said workpiece in planar relationship tosaid elastomer, the peripheral portion of said workpiece being upturnedwhen in planar relationship to said elastomer; and

c. means operatively connected to said elastomer for compressionthereof, said compression means including lower and upper elements, eachsaid upper and lower element formed with a hole having a profilecorresponding to said opening, said upper and lower elements havingoperative and inoperative positions, said elastomer being compressedwhen said upper and lower elements are in their operative positions,said compressed elastomer bulging into said opening and engaging theperiphery of said workpiece and reversely folding the periphery of saidworkpiece, said upper and lower elements are in their operativepositions when said upper member is in its inoperative position.

a 4 a: a:

1. An apparatus for making a reverse fold in a workpiece, said apparatuscomprising: a. an elastomer formed with an internal opening adapted forreception of said workpiece, the aperture profile of said opening beingslightly smaller than and substantially conforming to the peripheralprofile of said workpiece; b. means for positioning said workpiecewithin said opening, said means for positioning including upper andlower members, the profile of said upper member being smaller than theaperture profile of said opening, said upper member having operative andinoperative positions, said upper member engaging said workpiece when inits operative position and disengaging said workpiece when in itsinoperative position, said lower member having operative and inoperativepositions, said lower member engaging said workpiece when in itsoperative position, said upper and lower members cooperating to positionsaid workpiece in planar relationship to said elastomer, the peripheralportion of said workpiece being upturned when in planar relationship tosaid elastomer; and c. means operatively connected to said elastomer forcompression thereof, said compression means including lower and upperelements, each said upper and lower element formed with a hole having aprofile corresponding to said opening, said upper and lower elementshaving operative and inoperative positions, said elastomer beingcompressed when said upper and lower elements are in their operativepositions, said compressed elastomer bulging into said opening andengaging the periphery of said workpiece and reversely folding theperiphery of said workpiece, said upper and lower elements are in theiroperative positions when said upper member is in its inoperativeposition and said lower member is in its operative position.
 2. Theapparatus as claimed in claim 1 wherein said elastomer is siliconerubber.
 3. The apparatus as claimed in claim 1 including meansoperatively connected to said compression means and positioning meansfor selective control thereof.
 4. An apparatus for making a reverse foldin a workpiece, said apparatus comprising: a. an elastomer formed withan internal opening adapted for reception of said workpiece, theaperture profile of said opening being slightly smaller than andsubstantially conforming to the peripheral profile of said workpiece; b.means for positioning said workpiece within said opening, said means forpositioning including upper and lower members, the profile of said uppermember being smaller than the aperture profile of said opening, saidupper member having operative and inoperative positions, said uppermember engaging said workpiece when in its operative position anddisengaging said workpiece when in its inoperative position, said lowermember defining a support for the workpiece, said upper and lowermembers cooperating to position said workpiece in planar relationship tosaid elastomer, the peripheral portion of said workpiece being upturnedwhen in planar relationship to said elastomer; and c. means operativelyconnected to said elastomer for compression thereof, said compressionmeans including lower and upper elements, each said upper and lowerelement formed with a hole having a profile corresponding to saidopening, said upper and lower elements having operative and inoperativepositions, said elastomer being compressed when said upper and lowerelements are in their operative positions, said compressed elastomerbulging into said opening and engaging the periphery of said workpieceand reversely folding the periphery of said workpiece, said upper andlower elements are in their operative positions when said upper memberis in its inoperative position.